<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8" />
<title>Insert title here</title>
</head>
<body>
<form method="post" th:action="@{/pay}">
    <button type="submit"><img src="images/paypal.jpg" width="100px;" height="30px;"/></button>
</form>
</body>
</html>